1. Field of the Invention
The present invention relates to fuel checkers for receiving specimens of fuel tank contents, and more particularly to a filter assembly designed for use in conjunction with fuel tank checkers.
2. Description of the Related Art
As a recognized safety precaution, the nature of the fuel in aircraft gas tanks must be checked before each flight to determine the presence of any contaminating agents as well as the octane rating. In the past, this inspection has been effected by, for example, the opening of the tank quick drain valve, by any suitable means in allowing a portion of the fuel to flow outwardly for reception within any convenient type of container. A scrutiny of the withdrawn fuel by an experienced individual will readily indicate whether the fuel is clear or is contaminated, and, further, as to what the octane rating of such fuel might be since its coloration is indicative thereof. In addition to withdrawing a specimen of the fuel from each tank of the aircraft, it is desired that a sample be taken from the lowermost location in the gas system, so that such procedure requires considerable time as well as effort in the requisite removal of any portions of the cowling to obtain access to the valve and operation of the valve itself.
Also, the like testing of fuels in the tank of gasoline powered ground vehicles, for example, in the military field, tanks, jeeps, half-tracks, and the like, is a desirable practice for assuming optimum operation. In the past this was accomplished by the use of any convenient instrumentalities, with all the associated inconvenience and time-consumption.
These tasks were made more convenient by the design of more specialized fuel checker devices. U.S. Pat. No. 3,011,349, issued to D. W. Kratz, entitled “Composite Tool and Receptacle”, discloses a tool and receptacle for receiving specimens of aircraft gas tanks. The Kratz device utilizes an elongated body of circular cross-section with a closed lower end. The upper end edge is provided with a series of spaced apart, upwardly opening, generally U-shaped indentations or notches for engaging axially aligned actuating arms of a pet cock type quick drain valve. The elongated body is preferably formed of molded transparent plastic. The device has a screwdriver assembly integral to the bottom end of the elongated body which is handy during various operations typically involved with aircraft maintenance.
Present applicant, Robert M. Brodbeck, is the inventor of an improved fuel checker disclosed and claimed in U.S. Pat. No. 5,359,905, entitled Fuel Checker For Use With Pet Cock or Ball and Spring Drain Valves. The '905 apparatus comprises an elongated body of substantially circular cross-section. The body is fabricated of transparent molded material and is open at its upper end. The body is of tubular character through a portion of its length for defining a fuel-receiving compartment having a central axis and communicating with the open upper end of the body. The body has spaced-apart indentations in its upper end edge for alignment and cooperation with associated actuating arms of a pet cock drain valve, if such a pet cock drain valve is utilized. The tubular portion is closed at its lower end portion. A resilient semi-rigid rod is removably attached at a first end to the lower end portion of the tubular portion. The resilient rod extends along the central axis beyond the upper end edge of the body so as to engage and manipulate a ball and spring drain valve at a second end of the rod, if such a ball and spring drain valve is utilized. Additionally, the rod is supported at an intermediate portion thereof. Supporting the rod at the first end (lower end) provides much more effective use with ball and spring type drain valves making it much less flimsy and incapable of being pushed down the elongated body during use by the opposing force of the ball and spring valve.
Recently, the Environmental Protection Agency (EPA) has mandated that no fuel can be thrown out onto the tarmac ramp. Therefore, it has become desirable to pour the tested fuel back into the fuel tank. This is undesirable if the sample has water and/or other contaminants. Thus, one desires to filter out such contaminants and return the fuel to the tank.
In response to this problem Wing Aero Products, Inc. distributes what is referred to as “The GATS Jar”. The GATS Jar is a stand alone fuel checker/separator device that provides both checking and separation of water and other contaminants. It includes a cap that supports a separator screen that creates a barrier to the passage of water through it and certain particulate debris, but remains no obstacle to the flow of fuel. The GATS Jar; however, has an open end so that while not in use it is difficult to store the device due to the resultant fumes and potential dripping of residual fuel from it. Furthermore, it includes a plastic plunger that makes it less than substantial.